The present disclosure relates to a printer that is configured to perform printing on a printing medium by using heat, and to a non-transitory computer-readable medium.
A printer is known that is configured to perform printing on a printing medium by using a thermal line head that is provided with a plurality of heating elements. The heating elements for a single line of an image that will be formed are arrayed in a main scanning direction on the thermal line head. The printer may operate the thermal line head by applying an electric current to the heating elements to generate heat.
Methods have been proposed for limiting the power that is consumed when the thermal line head is operated. For example, a method is known that detects a number of ON dots in printing data for a single line and then, based on the detected number of ON dots, controls the number of the heating elements that are heated. An outline of the method will be explained. The plurality of the heating elements that are provided in the thermal line head are divided into a plurality of blocks. In a case where the number of the detected ON dots is low, the printer heats the heating elements in all of the blocks at the same time. In this case, the printing of the entire line will be performed all at once, so the time that will be required in order to print the line may be minimized. It may therefore become possible to feed the printing medium at high speed, so high-speed printing can be performed.
On the other hand, in a case where the number of the ON dots is large, the printer heats the heating elements at a different time for each block. In this case, the printing of the line will be performed by being divided into a plurality of rounds, so the time that will be required in order to print the line will become longer than in the case where the printing of the entire line is performed all at once. It may therefore be impossible to feed the printing medium at high speed. Accordingly, the printing medium may be fed at low speed. As described above, the printer may perform printing on the printing medium while switching the feed speed of the printing medium in accordance with the number of the detected ON dots.